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SOCKETPAIR(2)               BSD System Calls Manual              SOCKETPAIR(2)

     socketpair -- create a pair of connected sockets

     #include <sys/socket.h>

     socketpair(int domain, int type, int protocol, int socket_vector[2]);

     The socketpair() call creates an unnamed pair of connected sockets in the specified domain domain, of
     the specified type, and using the optionally specified protocol.  The descriptors used in referencing
     the new sockets are returned in socket_vector[0] and socket_vector[1].  The two sockets are indistin-guishable. indistinguishable.

     The socketpair() function returns the value 0 if successful; otherwise the value -1 is returned and the
     global variable errno is set to indicate the error.

     The call succeeds unless:

     [EAFNOSUPPORT]     The specified address family is not supported on this machine.

     [EFAULT]           The address socket_vector does not specify a valid part of the process address

     [EMFILE]           No more file descriptors are available for this process.

     [ENFILE]           No more file descriptors are available for the system.

     [ENOBUFS]          Insufficient resources were available in the system to perform the operation.

     [ENOMEM]           Insufficient memory was available to fulfill the request.

     [EOPNOTSUPP]       The specified protocol does not support creation of socket pairs.

     [EPROTONOSUPPORT]  The specified protocol is not supported on this machine.

     [EPROTOTYPE]       The socket type is not supported by the protocol.

     #include <sys/types.h>
     #include <sys/socket.h>

     The include file <sys/types.h> is necessary.

     pipe(2), read(2), write(2), compat(5)

     This call is currently implemented only for the UNIX domain.

     The socketpair() function call appeared in 4.2BSD.

4.2 Berkeley Distribution        June 4, 1993        4.2 Berkeley Distribution

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